#!/usr/bin/python # # Copyright (C) 2006 Google Inc. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. """Contains classes representing Atom elements. Module objective: provide data classes for Atom constructs. These classes hide the XML-ness of Atom and provide a set of native Python classes to interact with. Conversions to and from XML should only be necessary when the Atom classes "touch the wire" and are sent over HTTP. For this reason this module provides methods and functions to convert Atom classes to and from strings. For more information on the Atom data model, see RFC 4287 (http://www.ietf.org/rfc/rfc4287.txt) AtomBase: A foundation class on which Atom classes are built. It handles the parsing of attributes and children which are common to all Atom classes. By default, the AtomBase class translates all XML child nodes into ExtensionElements. ExtensionElement: Atom allows Atom objects to contain XML which is not part of the Atom specification, these are called extension elements. If a classes parser encounters an unexpected XML construct, it is translated into an ExtensionElement instance. ExtensionElement is designed to fully capture the information in the XML. Child nodes in an XML extension are turned into ExtensionElements as well. """ __author__ = 'api.jscudder (Jeffrey Scudder)' try: from xml.etree import cElementTree as ElementTree except ImportError: try: import cElementTree as ElementTree except ImportError: try: from xml.etree import ElementTree except ImportError: from elementtree import ElementTree import warnings # XML namespaces which are often used in Atom entities. ATOM_NAMESPACE = 'http://www.w3.org/2005/Atom' ELEMENT_TEMPLATE = '{http://www.w3.org/2005/Atom}%s' APP_NAMESPACE = 'http://purl.org/atom/app#' APP_TEMPLATE = '{http://purl.org/atom/app#}%s' # This encoding is used for converting strings before translating the XML # into an object. XML_STRING_ENCODING = 'utf-8' # The desired string encoding for object members. set or monkey-patch to # unicode if you want object members to be Python unicode strings, instead of # encoded strings MEMBER_STRING_ENCODING = 'utf-8' #MEMBER_STRING_ENCODING = unicode # If True, all methods which are exclusive to v1 will raise a # DeprecationWarning ENABLE_V1_WARNINGS = False def v1_deprecated(warning=None): """Shows a warning if ENABLE_V1_WARNINGS is True. Function decorator used to mark methods used in v1 classes which may be removed in future versions of the library. """ warning = warning or '' # This closure is what is returned from the deprecated function. def mark_deprecated(f): # The deprecated_function wraps the actual call to f. def optional_warn_function(*args, **kwargs): if ENABLE_V1_WARNINGS: warnings.warn(warning, DeprecationWarning, stacklevel=2) return f(*args, **kwargs) # Preserve the original name to avoid masking all decorated functions as # 'deprecated_function' try: optional_warn_function.func_name = f.func_name except TypeError: pass # In Python2.3 we can't set the func_name return optional_warn_function return mark_deprecated def CreateClassFromXMLString(target_class, xml_string, string_encoding=None): """Creates an instance of the target class from the string contents. Args: target_class: class The class which will be instantiated and populated with the contents of the XML. This class must have a _tag and a _namespace class variable. xml_string: str A string which contains valid XML. The root element of the XML string should match the tag and namespace of the desired class. string_encoding: str The character encoding which the xml_string should be converted to before it is interpreted and translated into objects. The default is None in which case the string encoding is not changed. Returns: An instance of the target class with members assigned according to the contents of the XML - or None if the root XML tag and namespace did not match those of the target class. """ encoding = string_encoding or XML_STRING_ENCODING if encoding and isinstance(xml_string, unicode): xml_string = xml_string.encode(encoding) tree = ElementTree.fromstring(xml_string) return _CreateClassFromElementTree(target_class, tree) CreateClassFromXMLString = v1_deprecated( 'Please use atom.core.parse with atom.data classes instead.')( CreateClassFromXMLString) def _CreateClassFromElementTree(target_class, tree, namespace=None, tag=None): """Instantiates the class and populates members according to the tree. Note: Only use this function with classes that have _namespace and _tag class members. Args: target_class: class The class which will be instantiated and populated with the contents of the XML. tree: ElementTree An element tree whose contents will be converted into members of the new target_class instance. namespace: str (optional) The namespace which the XML tree's root node must match. If omitted, the namespace defaults to the _namespace of the target class. tag: str (optional) The tag which the XML tree's root node must match. If omitted, the tag defaults to the _tag class member of the target class. Returns: An instance of the target class - or None if the tag and namespace of the XML tree's root node did not match the desired namespace and tag. """ if namespace is None: namespace = target_class._namespace if tag is None: tag = target_class._tag if tree.tag == '{%s}%s' % (namespace, tag): target = target_class() target._HarvestElementTree(tree) return target else: return None class ExtensionContainer(object): def __init__(self, extension_elements=None, extension_attributes=None, text=None): self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} self.text = text __init__ = v1_deprecated( 'Please use data model classes in atom.data instead.')( __init__) # Three methods to create an object from an ElementTree def _HarvestElementTree(self, tree): # Fill in the instance members from the contents of the XML tree. for child in tree: self._ConvertElementTreeToMember(child) for attribute, value in tree.attrib.iteritems(): self._ConvertElementAttributeToMember(attribute, value) # Encode the text string according to the desired encoding type. (UTF-8) if tree.text: if MEMBER_STRING_ENCODING is unicode: self.text = tree.text else: self.text = tree.text.encode(MEMBER_STRING_ENCODING) def _ConvertElementTreeToMember(self, child_tree, current_class=None): self.extension_elements.append(_ExtensionElementFromElementTree( child_tree)) def _ConvertElementAttributeToMember(self, attribute, value): # Encode the attribute value's string with the desired type Default UTF-8 if value: if MEMBER_STRING_ENCODING is unicode: self.extension_attributes[attribute] = value else: self.extension_attributes[attribute] = value.encode( MEMBER_STRING_ENCODING) # One method to create an ElementTree from an object def _AddMembersToElementTree(self, tree): for child in self.extension_elements: child._BecomeChildElement(tree) for attribute, value in self.extension_attributes.iteritems(): if value: if isinstance(value, unicode) or MEMBER_STRING_ENCODING is unicode: tree.attrib[attribute] = value else: # Decode the value from the desired encoding (default UTF-8). tree.attrib[attribute] = value.decode(MEMBER_STRING_ENCODING) if self.text: if isinstance(self.text, unicode) or MEMBER_STRING_ENCODING is unicode: tree.text = self.text else: tree.text = self.text.decode(MEMBER_STRING_ENCODING) def FindExtensions(self, tag=None, namespace=None): """Searches extension elements for child nodes with the desired name. Returns a list of extension elements within this object whose tag and/or namespace match those passed in. To find all extensions in a particular namespace, specify the namespace but not the tag name. If you specify only the tag, the result list may contain extension elements in multiple namespaces. Args: tag: str (optional) The desired tag namespace: str (optional) The desired namespace Returns: A list of elements whose tag and/or namespace match the parameters values """ results = [] if tag and namespace: for element in self.extension_elements: if element.tag == tag and element.namespace == namespace: results.append(element) elif tag and not namespace: for element in self.extension_elements: if element.tag == tag: results.append(element) elif namespace and not tag: for element in self.extension_elements: if element.namespace == namespace: results.append(element) else: for element in self.extension_elements: results.append(element) return results class AtomBase(ExtensionContainer): _children = {} _attributes = {} def __init__(self, extension_elements=None, extension_attributes=None, text=None): self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} self.text = text __init__ = v1_deprecated( 'Please use data model classes in atom.data instead.')( __init__) def _ConvertElementTreeToMember(self, child_tree): # Find the element's tag in this class's list of child members if self.__class__._children.has_key(child_tree.tag): member_name = self.__class__._children[child_tree.tag][0] member_class = self.__class__._children[child_tree.tag][1] # If the class member is supposed to contain a list, make sure the # matching member is set to a list, then append the new member # instance to the list. if isinstance(member_class, list): if getattr(self, member_name) is None: setattr(self, member_name, []) getattr(self, member_name).append(_CreateClassFromElementTree( member_class[0], child_tree)) else: setattr(self, member_name, _CreateClassFromElementTree(member_class, child_tree)) else: ExtensionContainer._ConvertElementTreeToMember(self, child_tree) def _ConvertElementAttributeToMember(self, attribute, value): # Find the attribute in this class's list of attributes. if self.__class__._attributes.has_key(attribute): # Find the member of this class which corresponds to the XML attribute # (lookup in current_class._attributes) and set this member to the # desired value (using self.__dict__). if value: # Encode the string to capture non-ascii characters (default UTF-8) if MEMBER_STRING_ENCODING is unicode: setattr(self, self.__class__._attributes[attribute], value) else: setattr(self, self.__class__._attributes[attribute], value.encode(MEMBER_STRING_ENCODING)) else: ExtensionContainer._ConvertElementAttributeToMember( self, attribute, value) # Three methods to create an ElementTree from an object def _AddMembersToElementTree(self, tree): # Convert the members of this class which are XML child nodes. # This uses the class's _children dictionary to find the members which # should become XML child nodes. member_node_names = [values[0] for tag, values in self.__class__._children.iteritems()] for member_name in member_node_names: member = getattr(self, member_name) if member is None: pass elif isinstance(member, list): for instance in member: instance._BecomeChildElement(tree) else: member._BecomeChildElement(tree) # Convert the members of this class which are XML attributes. for xml_attribute, member_name in self.__class__._attributes.iteritems(): member = getattr(self, member_name) if member is not None: if isinstance(member, unicode) or MEMBER_STRING_ENCODING is unicode: tree.attrib[xml_attribute] = member else: tree.attrib[xml_attribute] = member.decode(MEMBER_STRING_ENCODING) # Lastly, call the ExtensionContainers's _AddMembersToElementTree to # convert any extension attributes. ExtensionContainer._AddMembersToElementTree(self, tree) def _BecomeChildElement(self, tree): """ Note: Only for use with classes that have a _tag and _namespace class member. It is in AtomBase so that it can be inherited but it should not be called on instances of AtomBase. """ new_child = ElementTree.Element('') tree.append(new_child) new_child.tag = '{%s}%s' % (self.__class__._namespace, self.__class__._tag) self._AddMembersToElementTree(new_child) def _ToElementTree(self): """ Note, this method is designed to be used only with classes that have a _tag and _namespace. It is placed in AtomBase for inheritance but should not be called on this class. """ new_tree = ElementTree.Element('{%s}%s' % (self.__class__._namespace, self.__class__._tag)) self._AddMembersToElementTree(new_tree) return new_tree def ToString(self, string_encoding='UTF-8'): """Converts the Atom object to a string containing XML.""" return ElementTree.tostring(self._ToElementTree(), encoding=string_encoding) def __str__(self): return self.ToString() class Name(AtomBase): """The atom:name element""" _tag = 'name' _namespace = ATOM_NAMESPACE _children = AtomBase._children.copy() _attributes = AtomBase._attributes.copy() def __init__(self, text=None, extension_elements=None, extension_attributes=None): """Constructor for Name Args: text: str The text data in the this element extension_elements: list A list of ExtensionElement instances extension_attributes: dict A dictionary of attribute value string pairs """ self.text = text self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} def NameFromString(xml_string): return CreateClassFromXMLString(Name, xml_string) class Email(AtomBase): """The atom:email element""" _tag = 'email' _namespace = ATOM_NAMESPACE _children = AtomBase._children.copy() _attributes = AtomBase._attributes.copy() def __init__(self, text=None, extension_elements=None, extension_attributes=None): """Constructor for Email Args: extension_elements: list A list of ExtensionElement instances extension_attributes: dict A dictionary of attribute value string pairs text: str The text data in the this element """ self.text = text self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} def EmailFromString(xml_string): return CreateClassFromXMLString(Email, xml_string) class Uri(AtomBase): """The atom:uri element""" _tag = 'uri' _namespace = ATOM_NAMESPACE _children = AtomBase._children.copy() _attributes = AtomBase._attributes.copy() def __init__(self, text=None, extension_elements=None, extension_attributes=None): """Constructor for Uri Args: extension_elements: list A list of ExtensionElement instances extension_attributes: dict A dictionary of attribute value string pairs text: str The text data in the this element """ self.text = text self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} def UriFromString(xml_string): return CreateClassFromXMLString(Uri, xml_string) class Person(AtomBase): """A foundation class from which atom:author and atom:contributor extend. A person contains information like name, email address, and web page URI for an author or contributor to an Atom feed. """ _children = AtomBase._children.copy() _attributes = AtomBase._attributes.copy() _children['{%s}name' % (ATOM_NAMESPACE)] = ('name', Name) _children['{%s}email' % (ATOM_NAMESPACE)] = ('email', Email) _children['{%s}uri' % (ATOM_NAMESPACE)] = ('uri', Uri) def __init__(self, name=None, email=None, uri=None, extension_elements=None, extension_attributes=None, text=None): """Foundation from which author and contributor are derived. The constructor is provided for illustrative purposes, you should not need to instantiate a Person. Args: name: Name The person's name email: Email The person's email address uri: Uri The URI of the person's webpage extension_elements: list A list of ExtensionElement instances which are children of this element. extension_attributes: dict A dictionary of strings which are the values for additional XML attributes of this element. text: String The text contents of the element. This is the contents of the Entry's XML text node. (Example: This is the text) """ self.name = name self.email = email self.uri = uri self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} self.text = text class Author(Person): """The atom:author element An author is a required element in Feed. """ _tag = 'author' _namespace = ATOM_NAMESPACE _children = Person._children.copy() _attributes = Person._attributes.copy() #_children = {} #_attributes = {} def __init__(self, name=None, email=None, uri=None, extension_elements=None, extension_attributes=None, text=None): """Constructor for Author Args: name: Name email: Email uri: Uri extension_elements: list A list of ExtensionElement instances extension_attributes: dict A dictionary of attribute value string pairs text: str The text data in the this element """ self.name = name self.email = email self.uri = uri self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} self.text = text def AuthorFromString(xml_string): return CreateClassFromXMLString(Author, xml_string) class Contributor(Person): """The atom:contributor element""" _tag = 'contributor' _namespace = ATOM_NAMESPACE _children = Person._children.copy() _attributes = Person._attributes.copy() def __init__(self, name=None, email=None, uri=None, extension_elements=None, extension_attributes=None, text=None): """Constructor for Contributor Args: name: Name email: Email uri: Uri extension_elements: list A list of ExtensionElement instances extension_attributes: dict A dictionary of attribute value string pairs text: str The text data in the this element """ self.name = name self.email = email self.uri = uri self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} self.text = text def ContributorFromString(xml_string): return CreateClassFromXMLString(Contributor, xml_string) class Link(AtomBase): """The atom:link element""" _tag = 'link' _namespace = ATOM_NAMESPACE _children = AtomBase._children.copy() _attributes = AtomBase._attributes.copy() _attributes['rel'] = 'rel' _attributes['href'] = 'href' _attributes['type'] = 'type' _attributes['title'] = 'title' _attributes['length'] = 'length' _attributes['hreflang'] = 'hreflang' def __init__(self, href=None, rel=None, link_type=None, hreflang=None, title=None, length=None, text=None, extension_elements=None, extension_attributes=None): """Constructor for Link Args: href: string The href attribute of the link rel: string type: string hreflang: string The language for the href title: string length: string The length of the href's destination extension_elements: list A list of ExtensionElement instances extension_attributes: dict A dictionary of attribute value string pairs text: str The text data in the this element """ self.href = href self.rel = rel self.type = link_type self.hreflang = hreflang self.title = title self.length = length self.text = text self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} def LinkFromString(xml_string): return CreateClassFromXMLString(Link, xml_string) class Generator(AtomBase): """The atom:generator element""" _tag = 'generator' _namespace = ATOM_NAMESPACE _children = AtomBase._children.copy() _attributes = AtomBase._attributes.copy() _attributes['uri'] = 'uri' _attributes['version'] = 'version' def __init__(self, uri=None, version=None, text=None, extension_elements=None, extension_attributes=None): """Constructor for Generator Args: uri: string version: string text: str The text data in the this element extension_elements: list A list of ExtensionElement instances extension_attributes: dict A dictionary of attribute value string pairs """ self.uri = uri self.version = version self.text = text self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} def GeneratorFromString(xml_string): return CreateClassFromXMLString(Generator, xml_string) class Text(AtomBase): """A foundation class from which atom:title, summary, etc. extend. This class should never be instantiated. """ _children = AtomBase._children.copy() _attributes = AtomBase._attributes.copy() _attributes['type'] = 'type' def __init__(self, text_type=None, text=None, extension_elements=None, extension_attributes=None): """Constructor for Text Args: text_type: string text: str The text data in the this element extension_elements: list A list of ExtensionElement instances extension_attributes: dict A dictionary of attribute value string pairs """ self.type = text_type self.text = text self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} class Title(Text): """The atom:title element""" _tag = 'title' _namespace = ATOM_NAMESPACE _children = Text._children.copy() _attributes = Text._attributes.copy() def __init__(self, title_type=None, text=None, extension_elements=None, extension_attributes=None): """Constructor for Title Args: title_type: string text: str The text data in the this element extension_elements: list A list of ExtensionElement instances extension_attributes: dict A dictionary of attribute value string pairs """ self.type = title_type self.text = text self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} def TitleFromString(xml_string): return CreateClassFromXMLString(Title, xml_string) class Subtitle(Text): """The atom:subtitle element""" _tag = 'subtitle' _namespace = ATOM_NAMESPACE _children = Text._children.copy() _attributes = Text._attributes.copy() def __init__(self, subtitle_type=None, text=None, extension_elements=None, extension_attributes=None): """Constructor for Subtitle Args: subtitle_type: string text: str The text data in the this element extension_elements: list A list of ExtensionElement instances extension_attributes: dict A dictionary of attribute value string pairs """ self.type = subtitle_type self.text = text self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} def SubtitleFromString(xml_string): return CreateClassFromXMLString(Subtitle, xml_string) class Rights(Text): """The atom:rights element""" _tag = 'rights' _namespace = ATOM_NAMESPACE _children = Text._children.copy() _attributes = Text._attributes.copy() def __init__(self, rights_type=None, text=None, extension_elements=None, extension_attributes=None): """Constructor for Rights Args: rights_type: string text: str The text data in the this element extension_elements: list A list of ExtensionElement instances extension_attributes: dict A dictionary of attribute value string pairs """ self.type = rights_type self.text = text self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} def RightsFromString(xml_string): return CreateClassFromXMLString(Rights, xml_string) class Summary(Text): """The atom:summary element""" _tag = 'summary' _namespace = ATOM_NAMESPACE _children = Text._children.copy() _attributes = Text._attributes.copy() def __init__(self, summary_type=None, text=None, extension_elements=None, extension_attributes=None): """Constructor for Summary Args: summary_type: string text: str The text data in the this element extension_elements: list A list of ExtensionElement instances extension_attributes: dict A dictionary of attribute value string pairs """ self.type = summary_type self.text = text self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} def SummaryFromString(xml_string): return CreateClassFromXMLString(Summary, xml_string) class Content(Text): """The atom:content element""" _tag = 'content' _namespace = ATOM_NAMESPACE _children = Text._children.copy() _attributes = Text._attributes.copy() _attributes['src'] = 'src' def __init__(self, content_type=None, src=None, text=None, extension_elements=None, extension_attributes=None): """Constructor for Content Args: content_type: string src: string text: str The text data in the this element extension_elements: list A list of ExtensionElement instances extension_attributes: dict A dictionary of attribute value string pairs """ self.type = content_type self.src = src self.text = text self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} def ContentFromString(xml_string): return CreateClassFromXMLString(Content, xml_string) class Category(AtomBase): """The atom:category element""" _tag = 'category' _namespace = ATOM_NAMESPACE _children = AtomBase._children.copy() _attributes = AtomBase._attributes.copy() _attributes['term'] = 'term' _attributes['scheme'] = 'scheme' _attributes['label'] = 'label' def __init__(self, term=None, scheme=None, label=None, text=None, extension_elements=None, extension_attributes=None): """Constructor for Category Args: term: str scheme: str label: str text: str The text data in the this element extension_elements: list A list of ExtensionElement instances extension_attributes: dict A dictionary of attribute value string pairs """ self.term = term self.scheme = scheme self.label = label self.text = text self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} def CategoryFromString(xml_string): return CreateClassFromXMLString(Category, xml_string) class Id(AtomBase): """The atom:id element.""" _tag = 'id' _namespace = ATOM_NAMESPACE _children = AtomBase._children.copy() _attributes = AtomBase._attributes.copy() def __init__(self, text=None, extension_elements=None, extension_attributes=None): """Constructor for Id Args: text: str The text data in the this element extension_elements: list A list of ExtensionElement instances extension_attributes: dict A dictionary of attribute value string pairs """ self.text = text self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} def IdFromString(xml_string): return CreateClassFromXMLString(Id, xml_string) class Icon(AtomBase): """The atom:icon element.""" _tag = 'icon' _namespace = ATOM_NAMESPACE _children = AtomBase._children.copy() _attributes = AtomBase._attributes.copy() def __init__(self, text=None, extension_elements=None, extension_attributes=None): """Constructor for Icon Args: text: str The text data in the this element extension_elements: list A list of ExtensionElement instances extension_attributes: dict A dictionary of attribute value string pairs """ self.text = text self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} def IconFromString(xml_string): return CreateClassFromXMLString(Icon, xml_string) class Logo(AtomBase): """The atom:logo element.""" _tag = 'logo' _namespace = ATOM_NAMESPACE _children = AtomBase._children.copy() _attributes = AtomBase._attributes.copy() def __init__(self, text=None, extension_elements=None, extension_attributes=None): """Constructor for Logo Args: text: str The text data in the this element extension_elements: list A list of ExtensionElement instances extension_attributes: dict A dictionary of attribute value string pairs """ self.text = text self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} def LogoFromString(xml_string): return CreateClassFromXMLString(Logo, xml_string) class Draft(AtomBase): """The app:draft element which indicates if this entry should be public.""" _tag = 'draft' _namespace = APP_NAMESPACE _children = AtomBase._children.copy() _attributes = AtomBase._attributes.copy() def __init__(self, text=None, extension_elements=None, extension_attributes=None): """Constructor for app:draft Args: text: str The text data in the this element extension_elements: list A list of ExtensionElement instances extension_attributes: dict A dictionary of attribute value string pairs """ self.text = text self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} def DraftFromString(xml_string): return CreateClassFromXMLString(Draft, xml_string) class Control(AtomBase): """The app:control element indicating restrictions on publication. The APP control element may contain a draft element indicating whether or not this entry should be publicly available. """ _tag = 'control' _namespace = APP_NAMESPACE _children = AtomBase._children.copy() _attributes = AtomBase._attributes.copy() _children['{%s}draft' % APP_NAMESPACE] = ('draft', Draft) def __init__(self, draft=None, text=None, extension_elements=None, extension_attributes=None): """Constructor for app:control""" self.draft = draft self.text = text self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} def ControlFromString(xml_string): return CreateClassFromXMLString(Control, xml_string) class Date(AtomBase): """A parent class for atom:updated, published, etc.""" #TODO Add text to and from time conversion methods to allow users to set # the contents of a Date to a python DateTime object. _children = AtomBase._children.copy() _attributes = AtomBase._attributes.copy() def __init__(self, text=None, extension_elements=None, extension_attributes=None): self.text = text self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} class Updated(Date): """The atom:updated element.""" _tag = 'updated' _namespace = ATOM_NAMESPACE _children = Date._children.copy() _attributes = Date._attributes.copy() def __init__(self, text=None, extension_elements=None, extension_attributes=None): """Constructor for Updated Args: text: str The text data in the this element extension_elements: list A list of ExtensionElement instances extension_attributes: dict A dictionary of attribute value string pairs """ self.text = text self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} def UpdatedFromString(xml_string): return CreateClassFromXMLString(Updated, xml_string) class Published(Date): """The atom:published element.""" _tag = 'published' _namespace = ATOM_NAMESPACE _children = Date._children.copy() _attributes = Date._attributes.copy() def __init__(self, text=None, extension_elements=None, extension_attributes=None): """Constructor for Published Args: text: str The text data in the this element extension_elements: list A list of ExtensionElement instances extension_attributes: dict A dictionary of attribute value string pairs """ self.text = text self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} def PublishedFromString(xml_string): return CreateClassFromXMLString(Published, xml_string) class LinkFinder(object): """An "interface" providing methods to find link elements Entry elements often contain multiple links which differ in the rel attribute or content type. Often, developers are interested in a specific type of link so this class provides methods to find specific classes of links. This class is used as a mixin in Atom entries and feeds. """ def GetSelfLink(self): """Find the first link with rel set to 'self' Returns: An atom.Link or none if none of the links had rel equal to 'self' """ for a_link in self.link: if a_link.rel == 'self': return a_link return None def GetEditLink(self): for a_link in self.link: if a_link.rel == 'edit': return a_link return None def GetEditMediaLink(self): for a_link in self.link: if a_link.rel == 'edit-media': return a_link return None def GetNextLink(self): for a_link in self.link: if a_link.rel == 'next': return a_link return None def GetLicenseLink(self): for a_link in self.link: if a_link.rel == 'license': return a_link return None def GetAlternateLink(self): for a_link in self.link: if a_link.rel == 'alternate': return a_link return None class FeedEntryParent(AtomBase, LinkFinder): """A super class for atom:feed and entry, contains shared attributes""" _children = AtomBase._children.copy() _attributes = AtomBase._attributes.copy() _children['{%s}author' % ATOM_NAMESPACE] = ('author', [Author]) _children['{%s}category' % ATOM_NAMESPACE] = ('category', [Category]) _children['{%s}contributor' % ATOM_NAMESPACE] = ('contributor', [Contributor]) _children['{%s}id' % ATOM_NAMESPACE] = ('id', Id) _children['{%s}link' % ATOM_NAMESPACE] = ('link', [Link]) _children['{%s}rights' % ATOM_NAMESPACE] = ('rights', Rights) _children['{%s}title' % ATOM_NAMESPACE] = ('title', Title) _children['{%s}updated' % ATOM_NAMESPACE] = ('updated', Updated) def __init__(self, author=None, category=None, contributor=None, atom_id=None, link=None, rights=None, title=None, updated=None, text=None, extension_elements=None, extension_attributes=None): self.author = author or [] self.category = category or [] self.contributor = contributor or [] self.id = atom_id self.link = link or [] self.rights = rights self.title = title self.updated = updated self.text = text self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} class Source(FeedEntryParent): """The atom:source element""" _tag = 'source' _namespace = ATOM_NAMESPACE _children = FeedEntryParent._children.copy() _attributes = FeedEntryParent._attributes.copy() _children['{%s}generator' % ATOM_NAMESPACE] = ('generator', Generator) _children['{%s}icon' % ATOM_NAMESPACE] = ('icon', Icon) _children['{%s}logo' % ATOM_NAMESPACE] = ('logo', Logo) _children['{%s}subtitle' % ATOM_NAMESPACE] = ('subtitle', Subtitle) def __init__(self, author=None, category=None, contributor=None, generator=None, icon=None, atom_id=None, link=None, logo=None, rights=None, subtitle=None, title=None, updated=None, text=None, extension_elements=None, extension_attributes=None): """Constructor for Source Args: author: list (optional) A list of Author instances which belong to this class. category: list (optional) A list of Category instances contributor: list (optional) A list on Contributor instances generator: Generator (optional) icon: Icon (optional) id: Id (optional) The entry's Id element link: list (optional) A list of Link instances logo: Logo (optional) rights: Rights (optional) The entry's Rights element subtitle: Subtitle (optional) The entry's subtitle element title: Title (optional) the entry's title element updated: Updated (optional) the entry's updated element text: String (optional) The text contents of the element. This is the contents of the Entry's XML text node. (Example: This is the text) extension_elements: list (optional) A list of ExtensionElement instances which are children of this element. extension_attributes: dict (optional) A dictionary of strings which are the values for additional XML attributes of this element. """ self.author = author or [] self.category = category or [] self.contributor = contributor or [] self.generator = generator self.icon = icon self.id = atom_id self.link = link or [] self.logo = logo self.rights = rights self.subtitle = subtitle self.title = title self.updated = updated self.text = text self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} def SourceFromString(xml_string): return CreateClassFromXMLString(Source, xml_string) class Entry(FeedEntryParent): """The atom:entry element""" _tag = 'entry' _namespace = ATOM_NAMESPACE _children = FeedEntryParent._children.copy() _attributes = FeedEntryParent._attributes.copy() _children['{%s}content' % ATOM_NAMESPACE] = ('content', Content) _children['{%s}published' % ATOM_NAMESPACE] = ('published', Published) _children['{%s}source' % ATOM_NAMESPACE] = ('source', Source) _children['{%s}summary' % ATOM_NAMESPACE] = ('summary', Summary) _children['{%s}control' % APP_NAMESPACE] = ('control', Control) def __init__(self, author=None, category=None, content=None, contributor=None, atom_id=None, link=None, published=None, rights=None, source=None, summary=None, control=None, title=None, updated=None, extension_elements=None, extension_attributes=None, text=None): """Constructor for atom:entry Args: author: list A list of Author instances which belong to this class. category: list A list of Category instances content: Content The entry's Content contributor: list A list on Contributor instances id: Id The entry's Id element link: list A list of Link instances published: Published The entry's Published element rights: Rights The entry's Rights element source: Source the entry's source element summary: Summary the entry's summary element title: Title the entry's title element updated: Updated the entry's updated element control: The entry's app:control element which can be used to mark an entry as a draft which should not be publicly viewable. text: String The text contents of the element. This is the contents of the Entry's XML text node. (Example: This is the text) extension_elements: list A list of ExtensionElement instances which are children of this element. extension_attributes: dict A dictionary of strings which are the values for additional XML attributes of this element. """ self.author = author or [] self.category = category or [] self.content = content self.contributor = contributor or [] self.id = atom_id self.link = link or [] self.published = published self.rights = rights self.source = source self.summary = summary self.title = title self.updated = updated self.control = control self.text = text self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} __init__ = v1_deprecated('Please use atom.data.Entry instead.')(__init__) def EntryFromString(xml_string): return CreateClassFromXMLString(Entry, xml_string) class Feed(Source): """The atom:feed element""" _tag = 'feed' _namespace = ATOM_NAMESPACE _children = Source._children.copy() _attributes = Source._attributes.copy() _children['{%s}entry' % ATOM_NAMESPACE] = ('entry', [Entry]) def __init__(self, author=None, category=None, contributor=None, generator=None, icon=None, atom_id=None, link=None, logo=None, rights=None, subtitle=None, title=None, updated=None, entry=None, text=None, extension_elements=None, extension_attributes=None): """Constructor for Source Args: author: list (optional) A list of Author instances which belong to this class. category: list (optional) A list of Category instances contributor: list (optional) A list on Contributor instances generator: Generator (optional) icon: Icon (optional) id: Id (optional) The entry's Id element link: list (optional) A list of Link instances logo: Logo (optional) rights: Rights (optional) The entry's Rights element subtitle: Subtitle (optional) The entry's subtitle element title: Title (optional) the entry's title element updated: Updated (optional) the entry's updated element entry: list (optional) A list of the Entry instances contained in the feed. text: String (optional) The text contents of the element. This is the contents of the Entry's XML text node. (Example: This is the text) extension_elements: list (optional) A list of ExtensionElement instances which are children of this element. extension_attributes: dict (optional) A dictionary of strings which are the values for additional XML attributes of this element. """ self.author = author or [] self.category = category or [] self.contributor = contributor or [] self.generator = generator self.icon = icon self.id = atom_id self.link = link or [] self.logo = logo self.rights = rights self.subtitle = subtitle self.title = title self.updated = updated self.entry = entry or [] self.text = text self.extension_elements = extension_elements or [] self.extension_attributes = extension_attributes or {} __init__ = v1_deprecated('Please use atom.data.Feed instead.')(__init__) def FeedFromString(xml_string): return CreateClassFromXMLString(Feed, xml_string) class ExtensionElement(object): """Represents extra XML elements contained in Atom classes.""" def __init__(self, tag, namespace=None, attributes=None, children=None, text=None): """Constructor for EtensionElement Args: namespace: string (optional) The XML namespace for this element. tag: string (optional) The tag (without the namespace qualifier) for this element. To reconstruct the full qualified name of the element, combine this tag with the namespace. attributes: dict (optinal) The attribute value string pairs for the XML attributes of this element. children: list (optional) A list of ExtensionElements which represent the XML child nodes of this element. """ self.namespace = namespace self.tag = tag self.attributes = attributes or {} self.children = children or [] self.text = text def ToString(self): element_tree = self._TransferToElementTree(ElementTree.Element('')) return ElementTree.tostring(element_tree, encoding="UTF-8") def _TransferToElementTree(self, element_tree): if self.tag is None: return None if self.namespace is not None: element_tree.tag = '{%s}%s' % (self.namespace, self.tag) else: element_tree.tag = self.tag for key, value in self.attributes.iteritems(): element_tree.attrib[key] = value for child in self.children: child._BecomeChildElement(element_tree) element_tree.text = self.text return element_tree def _BecomeChildElement(self, element_tree): """Converts this object into an etree element and adds it as a child node. Adds self to the ElementTree. This method is required to avoid verbose XML which constantly redefines the namespace. Args: element_tree: ElementTree._Element The element to which this object's XML will be added. """ new_element = ElementTree.Element('') element_tree.append(new_element) self._TransferToElementTree(new_element) def FindChildren(self, tag=None, namespace=None): """Searches child nodes for objects with the desired tag/namespace. Returns a list of extension elements within this object whose tag and/or namespace match those passed in. To find all children in a particular namespace, specify the namespace but not the tag name. If you specify only the tag, the result list may contain extension elements in multiple namespaces. Args: tag: str (optional) The desired tag namespace: str (optional) The desired namespace Returns: A list of elements whose tag and/or namespace match the parameters values """ results = [] if tag and namespace: for element in self.children: if element.tag == tag and element.namespace == namespace: results.append(element) elif tag and not namespace: for element in self.children: if element.tag == tag: results.append(element) elif namespace and not tag: for element in self.children: if element.namespace == namespace: results.append(element) else: for element in self.children: results.append(element) return results def ExtensionElementFromString(xml_string): element_tree = ElementTree.fromstring(xml_string) return _ExtensionElementFromElementTree(element_tree) def _ExtensionElementFromElementTree(element_tree): element_tag = element_tree.tag if '}' in element_tag: namespace = element_tag[1:element_tag.index('}')] tag = element_tag[element_tag.index('}')+1:] else: namespace = None tag = element_tag extension = ExtensionElement(namespace=namespace, tag=tag) for key, value in element_tree.attrib.iteritems(): extension.attributes[key] = value for child in element_tree: extension.children.append(_ExtensionElementFromElementTree(child)) extension.text = element_tree.text return extension def deprecated(warning=None): """Decorator to raise warning each time the function is called. Args: warning: The warning message to be displayed as a string (optinoal). """ warning = warning or '' # This closure is what is returned from the deprecated function. def mark_deprecated(f): # The deprecated_function wraps the actual call to f. def deprecated_function(*args, **kwargs): warnings.warn(warning, DeprecationWarning, stacklevel=2) return f(*args, **kwargs) # Preserve the original name to avoid masking all decorated functions as # 'deprecated_function' try: deprecated_function.func_name = f.func_name except TypeError: # Setting the func_name is not allowed in Python2.3. pass return deprecated_function return mark_deprecated